scugpg Posted October 9, 2011 Report Posted October 9, 2011 Hey guys I have a 50hp Merc carburated 4 stroke and it seems to run rough at idle sometimes and occasionally stall out. Trolling around 3-5mph it sometimes misses. Running 2000rpm and above it runs great and seems to run better after going WOT for a little while. Changed the fuel filter, plugs, ran a bunch of seafoam through it this year. Runs better after plug change but still happens consistently. I also notice that the fuel bulb doesn't stay stiff on this motor...I've heard that this can be typical on these models but not sure. Has a built in fuel tank and put in a new fuel bulb this year. What else could be causing the issue? I know it was sitting quite a bit last year so hoping there isn't a bunch of water in the tank under the floor. Would be a real pain to pull the floor up. Any ideas? Thanks!
bushart Posted October 9, 2011 Report Posted October 9, 2011 I've got the same motor You may have the Ethanol blues---a degraded piece of crap in your carbs Took mine to a merc dealer who blew out the ports and reset the carbs--sorry hate to be the bearer of bad news PS I have the tiller so mines better
scugpg Posted October 9, 2011 Author Report Posted October 9, 2011 I have the tiller too Maybe I'll drain the carbs and add more sea foam. Do you have issues with the fuel bulb on that motor?
bushart Posted October 9, 2011 Report Posted October 9, 2011 The primer bulb on mine will get stiff---did you get the ethanol free bulb----no kiddin
scugpg Posted October 9, 2011 Author Report Posted October 9, 2011 It's an attwood ethanol resistant one....the old one did the same thing so thinking it's not the bulb
Tybo Posted October 9, 2011 Report Posted October 9, 2011 If it's a older engine.Replace all rubber fuel lines will ethanol suitable.
scugpg Posted October 10, 2011 Author Report Posted October 10, 2011 Did some troubleshooting today and it looks like something above the bulb causing it to lose prime. Where the fuel pump is I can hear hissing when I prime. It doesn't leak or seem like it's a gasket so maybe the pump check valve?
Garnet Posted October 10, 2011 Report Posted October 10, 2011 Dish soap and water. Spray hoses, connections. Look for bubbles.
scugpg Posted October 10, 2011 Author Report Posted October 10, 2011 Dish soap and water. Spray hoses, connections. Look for bubbles. Good point! I tightened the in/out connections at the fuel pump but could still hear hissing. It honestly sounded like it was from inside the housing but will give that a try its got to be somewhere. FYI on the fuel bulb, it will prime solid but go down a minute or two after priming....whether starting it or not.
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now